WATER SHIELD

(Brasenia schreberi), small, purple-flowered aquatic plant of the fanwort family (Cabombaceae), found in northern ponds and still waters throughout the world, except in Europe. "Water shield" also refers to fanwort (q.v.; Cabomba), the only other genus in the family Cabombaceae. Each oval, floating leaf of water shield is 5 to 10 centimetres (about 2 to 4 inches) long. A long, jelly-coated stem connects the middle of the leaf to rootstocks buried in mud. Several leafstalks of varying lengths rise from the main stalk. The flowers are small, 1.3 to 2 centimetres wide, and have three or four narrow petals; the small fruit is club shaped.